This invention relates to a surgical fixation device and techniques for its use, and more particularly to a tined fixation device and tined fixation device kit.
As illustrated in FIG. 1, the wrist joint 10 is formed at the intersection of the radius 15 and the ulna 20 with the metacarpals 25 and the carpals 30. The radius 15 includes an intramedullary canal 33 that runs the length of the radius. The canal 33 has a variable cross-sectional shape and cross-sectional diameter over its length. For example, the canal is wider and more oval shaped near the wrist joint but becomes rounded and narrower in the mid-region of the radius.
The wrist joint 10 and associated bones can be damaged, for example, in a fall. As illustrated in FIGS. 2a-d, a frequent injury to the wrist joint 10 is a distal radius fracture 35 in which a distal portion 40 of the radius is fractured away from the radius. Inherent bony instability, soft tissue damage, and frequent associated injuries make distal radius fractures very difficult to treat. Treatment of the fracture includes placement of a T-plate and external fixation, such as a cast. The functional outcome of the wrist joint after the treatment is generally directly related to residual deformity, both extra-articular alignment and intra-articular step-off, in the joint. FIGS. 2b-d illustrate various types of injuries according to the OTA classification system. For example, FIG. 2b illustrates a Type A injury, which occurs when the fracture line is along the plane of the epiphyseal plate. FIG. 2c illustrates a Type B injury, which occurs when the fracture line is along the margin of the joint. FIG. 2d illustrates a Type C injury, which occurs when the fracture line is along the plane of the epiphyseal plate, but also extends into the joint.
In one general aspect, a fixation plate kit for fixation of a distal radius facture includes a fixation plate and a matching tensioning device. The fixation plate includes an elongated plate having a distal portion and a proximal portion. The distal portion includes a first surface, a second surface extending from and forming an angle with the first surface, and at least one tine extending from the first surface. The proximal portion has a length and a width and is generally curved across its width along its length and includes at least one opening configured to receive a tensioning device. The tensioning device is configured to pass through the opening in the proximal portion, through a channel in a radius, and to be tightenable to fix the proximal portion to the radius.
Embodiments of the fixation plate kit may include one or more of the following features. For example, the kit may further include a screw configured to be inserted into bone tissue and the distal portion of the fixation plate may include a second opening configured to receive the screw. The second opening may include a radiused circumference and the screw may include a curved gimbal head configured to articulate against the radiused circumference. The screw may be a bicortical or a unicortical screw.
The tensioning device may include a shaft having an interlocking interface, a head, and a moveable lock configured to move in one direction along the shaft towards the head. The head may have a curved surface configured to articulate in a curved surface of the opening in the proximal portion. The tensioning device may be a molly bolt.
The fixation plate kit may further include a guide for drilling holes in bone to place the tine. The guide may include at least one drill guide and at least one tine cover and the drill guide may be configured to receive, orient, and offset a drill bit in the same orientation as the tine when the tine is inserted into the tine cover. The drill guide also may include at least one opening and an insert configured to be received in the opening.
The fixation plate kit may further include one of more of a drill bit configured to drill a hole in bone tissue, written instructions for use, an instructional video, a tensiometer mounted to the tine and configured to measure a tension in the tine, a monitor configured to receive a signal that is indicative of strain in the tine and that is transmitted by the tensiometer, a screw driver, and/or an allen wrench.
The fixation plate may include a therapeutic agent. The therapeutic agent may include one or both of a bone growth regulating protein and a platelet derived growth factor. The therapeutic agent may be coated on or applied to the plate or applied directly on the injury.
In another general aspect, the fixation plate, the fixation plate kit, and the embodiments of the fixation plate and kit described herein are used to repair a distal fracture of the radius.
In another general aspect, a fixation plate kit for fixation of a distal radius facture includes a fixation plate and an articulating member. The fixation plate includes an elongated plate having a distal portion and a proximal portion. The distal portion includes a first surface, a second surface extending from and forming an angle with the first surface, and at least one first opening in the first surface. The proximal portion includes a length and a width and is generally curved across its width over its length. The articulating member is configured to be mounted in the first opening, articulated relative to the first opening to extend from the distal portion over multiple angles and orientations, and inserted into a radius.
Embodiments of the fixation plate kit may include one or more of the following features. For example, the first opening may include an outwardly extending rounded surface and the articulating screw may include a head having a concave articulating portion configured to articulate against the rounded surface. The articulating portion may have an elongated or hemispherical shape.
The fixation plate kit may further include a screw configured to be inserted into bone tissue and the distal portion of the fixation plate includes a second opening configured to receive the screw. The second opening may include a radiused circumference and the screw may include a curved gimbal head configured to articulate against the radiused circumference. The screw may be a bicortical or a unicortical screw.
The fixation plate kit may further include a tensioning device configured to pass through an opening in the proximal portion, through a channel in a radius, and to be tightenable to fix the proximal portion to the radius. The tensioning device may include a shaft having an interlocking interface, a head, and a moveable lock configured to move in one direction along the shaft towards the head. The head may have a curved surface configured to articulate in a curved surface of the opening in the proximal portion. The tensioning device may be a molly bolt.
The fixation plate kit may further include one or more of written instructions for use, an instructional video, a screw driver, an alien wrench, a drill bit configured to drill a hole in bone tissue, a guide for drilling holes in bone to place the articulating member, and a tensiometer mounted to the articulating member and configured to measure a tension in the articulating member. The guide may include at least one opening and an insert configured to be received in the opening.
The tensiometer may be configured to transmit a signal indicative of strain in the articulating member and the fixation plate kit may further include a monitor that is configured to receive the signal.
The fixation plate may include a therapeutic agent. The therapeutic agent may include one or both of a bone growth regulating protein and a platelet derived growth factor. The therapeutic agent may be coated on or applied to the plate or applied directly on the injury.
In another general aspect, the fixation plate with articulating members, the associated fixation plate kit, and the embodiments of the fixation plate with articulating members and kit described herein are used to repair a distal fracture of the radius.
In another general aspect, a fixation plate kit for fixation of a distal radius facture includes a fixation plate and a member. The fixation plate includes an elongated plate having a distal portion and a proximal portion. The distal portion includes a first surface, a second surface extending from and forming an angle with the first surface, and at least one first opening in the first surface. The proximal portion has a length and a width and is generally curved across its width over its length. The member is configured to be mounted in the first opening, extend from the first opening, and be inserted into a radius.
Embodiments of the fixation plate kit may include any of the features described above. For example, the member may be integrally mounted in the first opening or may be an articulating member that extends from the distal portion over multiple angles and orientations.